Aight so [Frost] is undisputably one of the greatest Warframes of all time post (mini) rework.
This build is focused around gaining overguard & stripping armor with your 4, and then delivering a whole WORLD of hurt with your weapon of choice. My go-to is usually either the Exergis or Tenet Arca Plasmor if I'm feeling lazy, or if I'm looking to actively deal damage, any crit-based primary or secondary.
I run 2x Amber shards for casting speed, because that 4 animation is SLOOOOOW... and then 3 flex. Go nuts. [Frost] is very versatile.